Effects of Hydrolysis Reaction and Abrasive Drag Force Accelerator on Enhancing Si-Wafer Polishing Rate and Improving Si-Wafer Surface Roughness.

To satisfy the superior surface quality requirements in the fabrication of HBM (High-Bandwidth Memory) and 3D NAND Flash Memory, high-efficiency Si chemical mechanical planarization (CMP) is essential. In this study, a colloidal silica abrasive-based Si-wafer CMP slurry was developed to simultaneously achieve a high polishing rate (≥10 nm/min) and low surface roughness (≤0.2 nm) without inducing CMP-induced scratches.

The Chemical Deformation of a Thermally Cured Polyimide Film Surface into Neutral 1,2,4,5-Benzentetracarbonyliron and 4,4'-Oxydianiline to Remarkably Enhance the Chemical-Mechanical Planarization Polishing Rate.

The rapid advancement of 3D packaging technology has emerged as a key solution to overcome the scaling-down limitation of advanced memory and logic devices. Redistribution layer (RDL) fabrication, a critical process in 3D packaging, requires the use of polyimide (PI) films with thicknesses in the micrometer range. However, these polyimide films present surface topography variations in the range of hundreds of nanometers, necessitating chemical-mechanical planarization (CMP) to achieve nanometer-level surface flatness.

Real-Time Unsupervised Learning and Image Recognition via Memristive Neural Integrated Chip Based on Negative Differential Resistance of Electrochemical Metallization Cell Neuron Device.

Spiking neurons are essential for building energy-efficient biomimetic spatiotemporal systems because they communicate with other neurons using sparse and binary signals. However, the achievable high density of artificial neurons having a capacitor for emulating the integrate function of biological neurons has a limit. Furthermore, a low-voltage operation (<1.

Oxidative pyrolysis of alkali lignin using nitrogen functionalized graphene oxide-cerium oxide nanocatalysts: Mechanistic insights thorough density functional theory.

In this study, a functionalized graphene oxide-cerium oxide nanocatalysts (FGCe) with varying graphene oxide (GO) contents were prepared using an in-situ reflux method. The prepared nanocatalysts showcased improvement in the crystallinity and BET surface area values with increasing GO contents. The efficacies of prepared catalysts were investigated towards oxidative pyrolysis of alkali lignin in an ethanol-water system.

Thermally Induced Irreversible Disorder in Interlayer Stacking of γ-GeSe.

The interlayer stacking shift in van der Waals (vdW) crystals represents an important degree of freedom to control various material properties, including magnetism, ferroelectricity, and electrical properties. On the other hand, the structural phase transitions driven by interlayer sliding in vdW crystals often exhibit thickness-dependent, sample-specific behaviors with significant hysteresis, complicating a clear understanding of their intrinsic nature. Here, the stacking configuration of the recently identified vdW crystal, γ-GeSe, is investigated, and the disordering manipulation of stacking sequence is demonstrated.

Transferrable CsPbBr Perovskite Single-Crystalline Films for Visible-Wavelength Photodetectors.

In this study, we propose large-scale CsPbBr (CPB) single-crystalline films (SCFs) grown by a one-step vapor-phase epitaxy (VPE) method for application in optoelectronic devices. After optimizing the transport speed of the precursor and cooling rate, we obtained continuous CPB films with a lateral size exceeding 2 cm, and the thickness could be controlled from several micrometers to hundreds of nanometers. Crystallography and optoelectronic characterization proved the excellent crystallinity and very low trap density (2.

Unveiling the distinctive mechanical and thermal properties of γ-GeSe.

γ-GeSe is a newly identified polymorph among group-IV monochalcogenides, characterized by a distinctive interatomic bonding configuration. Despite its promising applications in electrical and thermal domains, the experimental verification of its mechanical and thermal properties remains unreported. Here, we experimentally characterize the in-plane Young's modulus (E) and thermal conductivity ([Formula: see text]) of γ-GeSe.

Performance and stability enhancement of perovskite photodetectors by additive and interface engineering using a dual-functional PPS zwitterion.

Hybrid organic-inorganic metal halide perovskites (HOIPs) have gained significant research interest due to their tunable optoelectronic properties and ease of fabrication. Enhancing the stability and efficiency of perovskite materials can be achieved through the passivation of defective surfaces and the improvement of interfacial properties. In this study, we introduce a zwitterionic compound, PPS (3-(1-pyridinio)-1-propanesulfonate), as a bifunctional material that serves as an additive and an interlayer.

Electrical Transport Properties Driven by Unique Bonding Configuration in γ-GeSe.

Group IV monochalcogenides have recently shown great potential for their thermoelectric, ferroelectric, and other intriguing properties. The electrical properties of group IV monochalcogenides exhibit a strong dependence on the chalcogen type. For example, GeTe exhibits high doping concentration, whereas S/Se-based chalcogenides are semiconductors with sizable bandgaps.

Efficient Propylene Carbonate Synthesis from Urea and Propylene Glycol over Calcium Oxide-Magnesium Oxide Catalysts.

A series of calcium oxide-magnesium oxide (CaO-MgO) catalysts were prepared under the effects of different precipitating agents and using varied Mg/Ca ratios. The physiochemical characteristics of the prepared catalysts were analyzed using XRD, FE-SEM, BET, FTIR, and TG/DTA techniques. Quantification of basic active sites present on the surface of the CaO-MgO catalysts was carried out using the Hammett indicator method.

Zinc hydroxystannate/zinc-tin oxide heterojunctions for the UVC-assisted photocatalytic degradation of methyl orange and tetracycline.

Partial phase modification of zinc hydroxystannate (ZHS) is an effective technique for improving its light absorption capacity. In this study, a zinc hydroxystannate/zinc-tin oxide (ZHS/ZTO) heterostructure was synthesized via chemical co-precipitation followed by annealing. The as-prepared heterostructure revealed cubic crystal morphology along with high-intensity diffraction peaks in the XRD pattern.

Evaluation of photocatalytic performances of PEG and PVP capped zinc sulfide nanoparticles towards organic environmental pollutant in presence of sunlight.

Advanced oxidation processes triggered by nanoscale materials are promising owing to the in-situ generation of reactive radicals that can degrade toxic organic pollutants. In the present study, zinc sulfide (ZnS) nanoparticles with polyethylene glycol-4000 (PEG-4000) and polyvinylpyrrolidone (PVP) cappings were prepared using the chemical precipitation method and characterized thoroughly. Optical and structural characteristics of the capped ZnS nanoparticles were investigated and compared with those of uncapped ZnS nanoparticles.

Improved Photoresponse Characteristics of a ZnO-Based UV Photodetector by the Formation of an Amorphous SnO Shell Layer.

Although ZnO nanostructure-based photodetectors feature a well-established system, they still present difficulties when being used in practical situations due to their slow response time. In this study, we report on how forming an amorphous SnO (a-SnO) shell layer on ZnO nanorods (NRs) enhances the photoresponse speed of a ZnO-based UV photodetector (UV PD). Our suggested UV PD, consisting of a ZnO/a-SnO NRs core-shell structure, shows a rise time that is 26 times faster than a UV PD with bare ZnO NRs under 365 nm UV irradiation.

Characterization of an Antibacterial Agent Targeting Ferrous Iron Transport Protein FeoB against and Gram-Positive Bacteria.

The emergence of multidrug-resistant strains has become a serious clinical problem. Iron is absolutely required for the bacterial growth, virulence associated with colonization, and survival from the host immune system. The FeoB protein is a major iron permease in bacterial ferrous iron transport systems (Feo) that has been shown to play a crucial role in virulence of some pathogenic bacteria.

Biochemical characterization of bacterial FeoBs: A perspective on nucleotide specificity.

Iron is an essential requirement for the survival and virulence of most bacteria. The bacterial ferrous iron transporter protein FeoB functions as a major reduced iron transporter in prokaryotes, but its biochemical mechanism has not been fully elucidated. In the present study, we compared enzymatic properties of the cytosolic portions of pathogenic bacterial FeoBs to elucidate each bacterial strain-specific characteristic of the Feo system.

Ultraviolet photodetector using pn junction formed by transferrable hollow n-TiO nano-spheres monolayer.

We report an ultraviolet (UV) photodetector with a universally transferable monolayer film with ordered hollow TiO spheres on p-GaN. After forming a TiO monolayer film by unidirectional rubbing of hollow TiO spheres on a polydimethylsiloxane (PDMS) supporting plate, we used a 5% polyvinyl alcohol (PVA) aqueous solution to transfer the film onto the target substrate. The PVA/TiO monolayer film was detached from the PDMS film and transferred to the p-GaN/AlO substrate.

Enhanced light extraction from GaN based light-emitting diodes using a hemispherical NiCoO lens.

We report on the improvement of light extraction efficiency from GaN-based light-emitting diodes (LEDs) using Ni(1-x)Co(x)O nanoparticles (NPs) formed on the p-GaN layer. After formation of Ni(1-x)Co(x)O hemispherical lens arrays on the blue LEDs by drop-casting colloidal NPs, electroluminescence (EL) and photoluminescence (PL) measurements are conducted to investigate the electrical and optical properties. The PL and EL intensities from the blue LEDs with the Ni(1-x)Co(x)O NPs are 1.

Structural and optical property studies on indium doped ZnO nanostructures for solution based organic-inorganic hybrid p-n junctions.

In doped ZnO nanocrystallites have established through a facile, low cost and high yield wet-chemical route. The X-ray diffraction measurements revealed the samples to be well crystallized, with a considerable shift in the prominent peak positions, indicating the successful substitution of In ions into the ZnO matrix. The particulate characteristic of the nanostructures was evaluated through the aid of electron microscopes, which revealed both the pristine and In doped ZnO nanocrystals to possess similar morphologies.

Enhancement of photoluminescence intensity of GaN-based light-emitting diodes with coated polystyrene/silica core-shell nanostructures.

We report the enhancement of the photoluminescence (PL) intensity of GaN-based light-emitting diode (LED) structures by using of a surface coating of polystyrene (PS)/silica (SiO2) core-shell nanospheres. PS/SiO2 core-shell nanosphere-coated LEDs show the highest PL intensity among various type LEDs. The relative PL intensity of PS/SiO2 core-shell nanosphere-coated LEDs increased by 10% and 14% compared with that of LEDs coated with only SiO2 nanospheres and conventional LEDs without any nanostructures, respectively.

Less strained and more efficient GaN light-emitting diodes with embedded silica hollow nanospheres.

Light-emitting diodes (LEDs) become an attractive alternative to conventional light sources due to high efficiency and long lifetime. However, different material properties between GaN and sapphire cause several problems such as high defect density in GaN, serious wafer bowing, particularly in large-area wafers, and poor light extraction of GaN-based LEDs. Here, we suggest a new growth strategy for high efficiency LEDs by incorporating silica hollow nanospheres (S-HNS).

Vertical array of ZnO submicrorods on periodically polarity-inverted templates using solution method.

Vertically aligned ZnO nano/submicrorods are grown on periodically polarity-inverted (PPI) ZnO templates by a solution-based growth method without any catalyst. For the selective growth of ZnO submicrorods, PPI ZnO structures are used for templates made by using a polarity control technique of ZnO with CrN and Cr2O3 intermediate layers. After syntheses of ZnO nanostructures on PPI ZnO, the vertically aligned ZnO rods were grown only onto the Zn-polar regions.

Catalyst-free metal-organic chemical vapor deposition growth of InN nanorods.

We demonstrated the successful growth of catalyst-free InN nanorods on (0001) Al2O3 substrates using metal-organic chemical vapor deposition. Morphological evolution was significantly affected by growth temperature. At 710 degrees C, complete InN nanorods with typical diameters of 150 nm and length of approximately 3.

Second harmonic generation in periodically polarity-inverted zinc oxide.

We report on the second harmonic generation (SHG) in 2D periodically polarity-inverted (PPI) ZnO heterostructures. The grating structures with nanometer-scale periodicity are fabricated on (0001) Al(2)O(3) substrates by using the in situ polarity inversion method. The achievements of SHG with grating in fabricated PPI ZnO structures are demonstrated under consideration of quasi phase matching conditions.